Hilary Duff's Son Luca, 4.5 Months, Is Teething!

USMagazine, Sunday, August 12, 2012, 1:15pm (PDT)

Hilary Duff was quick to share her proud mommy moment with her Twitter followers on Thursday as her son, Luca, reached his latest milestone.

"Luca is cutting a tooth!!! It's the cutest/saddest (because it hurts) getting so big my boy!! Gunna have a little toof lol," the 24-year-old first-time mom shared about her and hubby Mike Comrie's 4.5-months-old son.

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The first-time parents, who wed in 2010 and will celebrate their second wedding anniversary on Tuesday, are loving life as a family of three and Duff gushed about things in an interview earlier this summer.

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"It's made [our marriage] stronger," she told Hollyscoop about her relationship with Comrie, 31. "Having a baby is a lot of hard work and you really depend on each other for a lot. There is so much love . . . you can't imagine it until it happens to you and you look at your husband and you're like, 'We did this together.'"

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Although Duff is busy tending to her mom duties, she's making time for another baby -- her fourth studio album!

"Rushing to the studio to record…!!!" she shared via Twitter in late July. The new album would mark the Lizzie Mcguire alum's first return to music since her 2007 release, Dignity, which featured singles "Play with Fire," "With Love," and "Stranger."

This article originally appeared on Usmagazine.com: Hilary Duff's Son Luca, 4.5 Months, Is Teething!